With a big cheering section from the Hotel and Restaurant Employees Union and the imposing presence of New York Jets headliners, Mayor Bloomberg and Governor Pataki made their pitch for a West Side stadium on Thursday morning at the Javits Convention Center

A short time later, Assemblymember Richard Gottfried and City Councilmember Christine Quinn led a group of elected officials and vociferous residents of Chelsea and Clinton in an anti-stadium news conference two blocks away at a low-income housing complex.

Gottfried and Quinn, along with Councilmember Philip Reed from the Upper West Side, Assemblymember Adriano Espaillat from Washington Heights and State Senator Liz Krueger, vowed to fight the stadium in the Council and the state Legislature and, if necessary, in the courts.

Were here with a clear message for the mayor and the governor that this is our neighborhood and we do not want a stadium, said Quinn, adding, We are in favor of expanding the convention center in a responsible way. Opponents fear the stadium would cause traffic problems that would overwhelm the neighborhood and impact much of the rest of Manhattan.

But the mayor insisted at the earlier news conference that the stadium, to be built on a platform over the rail yards south of the convention center, was an indispensable part of the Hudson Yards Redevelopment.

Yes, for eight Sundays in the fall, or 10 if the Jets make the playoffs, it will be a football stadium but it will also give us the capacity to hold the Super Bowl and serve as the Olympic Stadium in 2012, said the mayor to a cheering crowd that included Jets quarterback Chad Pennington, coach Herman Edwards and Paul Tagliabue, the National Football League commissioner.

Jets owner, Woody Johnson, was there too, on the platform with the governor; the mayor; Charles Gargano, the Empire State Development Corp.s president; Peter Ward, business manager of Local 6 Hotel and Restaurant Employees; and Joseph Spinnato, head of the Hotel Industry Association.

Im going to ask Paul Tagliabue if we cant have a Super Bowl here in a few years, the mayor said, receiving an encouraging nod from the commissioner. The plan is to complete the stadium in 2009.

The Hudson Yards redevelopment calls for extending the No. 7 subway line to 11th Ave. and down to 34th St., creating a new north-south boulevard with parks, as well as new zoning to encourage high-rise office towers along 11th Ave.

It will produce 42,000 construction jobs and 17,000 permanent jobs, said the mayor of the redevelopment plan.

The stadium and convention center expansion, the mayor said, would catapult the convention center from 18th largest in the nation to fifth, enabling the Javits to accommodate the large shows that it has never been able to win.

The cost of the Hudson Yards plan would include $1.4 billion for the stadium and platform over the rail yards, with the city and state paying $300 million each to build the platform and to cover the cost of the stadiums retractable roof. The Jets would pay $800 million to build the stadium itself.

The Hudson Yards big-ticket item is the $1.96 billion subway extension, which the governor and the mayor also deem an indispensable element. The new boulevard between 10th and 11th Aves. and a system of north-south parks and a plaza on a platform over the eastern part of the rail yards is expected to cost $407 million.

The financing plan includes $500 million from the hotel industry generated by a $1.50 per room hotel surcharge and the sale of air rights over the rail yards to developers for 11th Ave. office towers. Tax-exempt bonds based on developers payments in lieu of taxes, or pilots, would be issued to finance the project.

Just before the news conference on Thursday, the Metropolitan Transportation Authority signed a memorandum of agreement with E.S.D.C. and the Jets to allow construction of the platform over the rail yards between 12th and 11th Aves. from 30th to 33rd Sts. for the multi-purpose sports, entertainment and exhibition facility, as the stadium is officially known.

The broad agreement, which still requires approval by the boards of directors of the E.S.D.C. and the M.T.A., includes provisions authorizing the sale of air rights. The agreement does not specify which agency will benefit from the air rights sale. The agreement also states the M.T.A. would receive unspecified ground-lease rent for use of the rail yards.

The stadium would have a capacity for 75,000 football fans, 85,000 Olympic spectators and could serve as a 180,000-sq.-ft. exposition hall with 30,000 sq. ft. of meeting room space.

Despite the confidence of the Bloomberg and Pataki administrations that the stadium and the redevelopment will happen, opponents said they would not give up.

At the anti-stadium conference, Assemblymember Gottfried, who represents the convention center neighborhood and supports expansion of the center but opposes the stadium, said the governor failed to mention that the Legislature has a role in the approval of the project.

None of this package is going to move without the governors asking the support of the Assembly and the State Senate, said Gottfried, and thats not going to happen with a stadium in the project.

Quinn also reminded opponents that the City Council would have to approve the new zoning.

Moreover, the Bloomberg administration plans to use $350 million in future surplus revenues of the Battery Park City Authority to secure the bonds that finance the convention center expansion.

But the bond plan needs the approval of City Comptroller William Thompson as well as the mayor and the B.P.C.A. board of directors.

While James Gill, B.P.C.A. chairperson, said he favored using authority revenue to back the bonds, he emphasized that the bonds would be used only for the Javits expansion, not for the stadium. However, the stadium is being justified because it would serve as convention center space most of the year.

Thompson was noncommittal. His office acknowledged on Thursday that it was studying the proposal to use B.P.C.A. revenues. But Thompson said later that he was skeptical about the stadium part of the project. I dont know that the stadium returns a lot of additional revenue, he told New York News Network. I dont care how anyone tries to dress it up  as an adjunct to the Javits and a bunch of other things  its a 75,000-seat stadium.

Assembly Speaker Sheldon Silver said he was adamantly opposed to using B.P.C.A. funds for the $1.4 billion project. This money is desperately needed for the revitalization of Downtown and failing to do so will have dire consequences, Silver said in a statement. It is nothing less than a blatant slap in the face to the people who lived through the tragic events of Sept. 11, 2001, he said. The money should be used for elementary and middle schools, community centers and park improvements, Silver said.

Silver also said he had serious concerns and reservations about the entire Hudson Yards project, which includes reconfiguring a 50-block area and new zoning to encourage high-rise commercial towers between 30th and 43rd Sts.

Assemblymember Deborah Glick and State Senator Tom Duane also weighed in against the stadium. Glick, in a statement issued on Thursday, called the stadium an outrageous waste of resources. At a time when a crisis in affordable housing faces low- and middle-income New Yorkers and homelessness in New York City has reached its highest levels, this plan is particularly misguided, Glick said.